The
present Plymouth Light—also known as Gurnet Light—is located 3.8
nautical miles northeast of Plymouth, Massachusetts. The Gurnet was
built in 1768 with two lights on the property of John and Hannah
Thomas, who also became the first lighthouse-keepers; however the
lights were too close together and from a distance could only be
seen as a merged, single beam of light. In 1778, the lighthouse was
struck by a cannonball and was repaired. In 1790 the state turned
the lighthouse over to the federal government who installed the
first woman lighthouse-keeper. The lighthouse burned in 1801 and the
government then rebuilt it as twin towers. In 1842 the crumbling
towers were replaced with two white octagonal pyramidal towers. The
lights were 70 feet above sea level. However, the problem of the
"merging lights" remained. In 1871 a fourth-order fresnal lens was
installed, greatly increasing the strength of the lights. In 1914
the Cape Cod Canal opened, giving new importance to the Gurnet as a
navigational aid. In 1924 the Bureau of Lighthouses discontinued one
of the twin lights as it phased out multiple lights. The remaining
light still stands. In 1997 the Coast Guard moved the lighthouse
back from the eroding 45-foot cliff. It was standing only 50 feet
from the edge when it was placed on rollers and moved by tracks 140
feet from its previous site. It now sits on the property of Fort
Andrews at Gurnet Point. In 1999, the Coast Guard turned Gurnet
Light over to Project Bug Light. The original 4th order Fresnel lens
is on display at the Hull Lifesaving Museum in Hull, Massachusetts.